The control of intake valve deposits (IVD), combustion chamber deposits (CCD), and the octane requirement increase (ORI) attributable to CCD has long been a subject of concern to engine and vehicle manufacturers, fuel processors and the public and is extensively addressed in the literature. Solutions to this problem and related problems of knock, have taken the form of novel gasoline additives such as detergents, anti-corrosives, octane requirement reducing additives, deposit control additives and numerous combinations of additives. Other approaches modify intake valve and combustion chamber configurations.
Traditional IVD control additives are based on the use of detergents such as polyisobutylene amine (PIBA) and polyether amines (PEA). These detergents effectively disperse and solubilize the growing carbonaceous deposit and operate efficiently when there is ample washing of the intake valve by gasoline containing one of these detergents. However, these additives contribute to CCD. The combination of alkoxylates with PIBA and PEA facilitates their controlled decomposition along with the simultaneous decomposition of deposit precursors on combustion chamber walls.
Gasoline detergents are now required in the United States for controlling deposit formation on auto engine intake valves. There is current interest in developing new detergent-based additive packages that can simultaneously and optimally control both IVD and CCD. Thus, a reasonably priced additive with greater reduction of IVD and CCD is desirable.